List vertex colors from a bmesh
Each loop (= corner of a poly) has its own vertex color. You can print the vertex color for each corner with
# Get the first Vertex Color layer; can also use its name (eg. &quot;Col&quot;)
layer = bm.loops.layers.color[0]

for face in bm.faces:
    for loop in face.loops:
        color = loop[layer]  # gives a Vector((R, G, B, A))
        print(color)

Btw, if possible you should get the triangulation with calc_loop_triangles instead, since it gives you the triangulation that Blender actually draws.